As a power conversion device of this type, for example, there has been proposed a three-level power conversion device in which a power conversion circuit for one phase includes electrolytic capacitors which serve as a direct current power supply, an insulated gate bipolar transistor (IGBT) module having a 2-in-1 configuration in which a first IGBT to which a free-wheeling diode is connected in reverse parallel and a second IGBT to which a free-wheeling diode is connected in reverse parallel in a similar manner are connected to each other in series and housed in one package, and one or a plurality of bi-directional switch modules which house in a package a bi-directional switch having a property of allowing the current to flow in a bi-directional manner. (e.g., see WO 2011/061813).
In a conventional technique as disclosed in WO 2011/061813, the IGBT module and the bi-directional switch module which constitute the power conversion circuit for one phase are electrically connected to each other by laminated conductors having a flat plate shape. These laminated conductors are configured to have a three-layer wiring structure having a P conductor, an N conductor, and a wiring conductor for the bi-directional switch which is disposed between these P conductor and N conductor and divided into three pieces or two pieces.